EP0019507A1 - Verbesserung kapazitiver Spannungstransformatoren mit elektronischem Ausgang - Google Patents

Verbesserung kapazitiver Spannungstransformatoren mit elektronischem Ausgang Download PDF

Info

Publication number
EP0019507A1
EP0019507A1 EP80400554A EP80400554A EP0019507A1 EP 0019507 A1 EP0019507 A1 EP 0019507A1 EP 80400554 A EP80400554 A EP 80400554A EP 80400554 A EP80400554 A EP 80400554A EP 0019507 A1 EP0019507 A1 EP 0019507A1
Authority
EP
European Patent Office
Prior art keywords
voltage
divider
signal
capacitive
current
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP80400554A
Other languages
English (en)
French (fr)
Other versions
EP0019507B1 (de
Inventor
Philippe Despiney
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Safran Data Systems SAS
Original Assignee
Enertec SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Enertec SA filed Critical Enertec SA
Publication of EP0019507A1 publication Critical patent/EP0019507A1/de
Application granted granted Critical
Publication of EP0019507B1 publication Critical patent/EP0019507B1/de
Expired legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
    • G01R15/04—Voltage dividers
    • G01R15/06—Voltage dividers having reactive components, e.g. capacitive transformer

Definitions

  • the present invention relates to capacitive voltage dividers and more particularly to dividers whose output voltage is picked up by an electronic amplifier capable of delivering on an inductive load.
  • the voltage across the terminals of the second capacitor C2, called the secondary capacitor, represents a fraction of the primary voltage, the ratios of the capacitors Cl and C2 defining the division ratio between the primary and secondary voltages.
  • This type of divider has a particularly useful application in transformers for measuring very high voltages. It makes it possible to carry out very high voltage measurements at the primary level by sampling the secondary voltage without resorting to magnetic transformers capable of supporting these high voltages with the corresponding isolation devices.
  • the secondary voltage taken from the terminals of the capacitor C2 supplies the primary of an induction transformer which achieves an additional reduction. mental tension.
  • the capacitive divider is part of a capacitive voltage transformer connected between a high-voltage line and the earth, the tripping of the latter at its two ends eliminates all possibility for the loads of capacities C1 and C2 to run out.
  • the capacities, and in particular the capacity C1 can remain charged for extremely long periods, only extremely low leakage currents allowing the flow of the charges.
  • the interruption of the supply voltage can cause, depending on the case, two types of harmful effects insofar as they give rise to transient phenomena during recovery of the supply voltage.
  • These transient phenomena can come, as the case may be, either from an imbalance existing between the states of charge of Cl and C2 at the time of the voltage recovery, or from the saturation of the magnetic transformer output of the electronic amplifier under the effect of the DC voltage (very high) which was present at the output of the amplifier when the supply voltage was interrupted leaving the capacitor C2 charged.
  • the input voltage of the electronic amplifier is maintained at a maximum value in continuous mode.
  • Each of the capacitors C1 and C2 has an armature connected to a common junction terminal M. Between the terminals M and B is connected an electronic amplification device Al for taking the secondary voltage v e (voltage at the terminals of the capacitor C2).
  • the amplitude ratio of the voltage v e to the voltage vp is determined by the values of the capacitors C1 and C2. It remains constant for the instantaneous values of v P and v e and independent of the regime, alternating or aperiodic, of the voltage v P if the input impedance of the electronic device Al connected to the terminals M and B is sufficiently high.
  • the electronic amplifier A1 conventionally comprises an input resistor R1 one end of which is connected to the terminal M, an operational amplifier Pl mounted at the input between the terminal B and the other end F1 of the resistor R1 and a resistor of against reaction R'1.
  • the output S1 of the amplifier P1 flows on a magnetic voltage transformer T to supply an output voltage v s to means of use thus galvanically isolated from the capacitive divider proper.
  • the switch D is closed and its opening causes the interruption of the supply voltage of the capacitive divider. It is possible that this opening occurs at the time when the amplitude of the alternating supply voltage reached a relatively high value and in particular in the vicinity of its peak value.
  • each of the two capacitors C1 and C2 is charged at a high value respectively determined by its voltage at the terminals when the alternating supply between the points A and B is interrupted.
  • the switch D remains open, the discharge of the capacitor C1 can only take place under the effect of leakage currents with a time constant which can be considerable.
  • Te is assumed to be low first, the voltage across the capacitor will decrease and the transformer T will be supplied with a voltage corresponding to the output of the amplifier Al. If the transformer is sufficiently dimensioned and the voltage across the terminals of C2 decreasing rapidly enough, the transformer will be able to withstand the aperiodic appearing at its terminals without damage.
  • a possible solution to avoid saturation of the transformer T, under the effect of the charges trapped in the capacitor C2 at the time of the interruption of the supply voltage at a level of high amplitude, would consist in placing a high-pass filter at the input of the amplifier Al in order to avoid the application to the latter of the DC component of the voltage across the terminals of C2.
  • a high-pass filter at the input of the amplifier Al in order to avoid the application to the latter of the DC component of the voltage across the terminals of C2.
  • such a filter creates a phase shift between the detected voltage across the capacitor C2 and the output of the amplifier Al, which is detrimental to the faithful representation of the primary voltage by the output voltage of the transformer.
  • FIG. 2 is shown a capacitive voltage transformer connected between a point Lo of a high voltage line and the earth To and comprising a capacitive divider formed by capacitors C1 and C2 in series between the points Lo and To.
  • the transformers Voltage capacitors (TCT) are well known and the present description does not require a detailed description of their structure.
  • an impedance Z whose ends are designated by G and H,.
  • the input E2 of the amplifier Al is connected to the point G by a conductor 40.
  • the input El of the amplifier A1 is connected to the point M by a line 42 through an amplifier A2 and a switch L32 on the connection of terminal M at input resistance R2 of A2.
  • the voltage across terminals M and G of capacitor C2 of the capacitive divider, voltage designated by v as in fig. 1 is normally applied, when the switch L32 is closed, to the inputs of the amplifier Al.
  • This amplifier of high impedance, transforms this signal v e into an input signal of the primary of the magnetic transformer T.
  • the amplifier A2 comprises, in addition to the input resistor R2, an operational amplifier P2, one input of which is connected to the output F2 of the resistor R2 and the other input of which is connected at a point 44 to line 40, an output S2 for P2 on line 42 and a counter-resistance R'2 connected between points F2 and S2.
  • This voltage v i is applied to an amplifier A3, of construction similar to that of the amplifier A2, and comprising an input resistance R3 of which one end is connected to H, an operational amplifier P3 of which an input is connected to the other end F3 of the resistor R3 and the other input is connected to terminal 44 on line 40, the output of this amplifier P3 being designated by S3, and a feedback resistor R'3 connected between F3 and S3.
  • the signal at the output S3 of the amplifier A3 is applied to a rectification and filtering circuit 50 which performs on the one hand the full-wave rectification and on the other hand applies a slight filtering to the signal thus rectified so as to obtain an output voltage v 2 between the output 52 of the RF filter rectifier circuit 50 and the reference line 40, the shape of which is represented for example in the wave diagrams of FIGS. 3 and 4.
  • the signal v 2 is influenced by the peak value of the input signal v i representative of the current and tends to envelop the upper part of the rectified wave (the latter is dotted in Figs. 3 and 4 .).
  • the voltage signal present at the output S2 of the amplifier A2 is also applied to an RF rectification and filtering circuit 60 which performs full wave rectification and slight filtering to deliver at its output 62 a voltage signal v 1 by with respect to the voltage of the reference line 40 which is represented on the wave diagrams of FIGS. 3 and 4.
  • the impedance Z chosen to detect the current in the example described being a resistance, it is noted that in both cases of the figures described, the half-wave reshaped signals but before filtering (shown in dotted lines) v and v 2 are in phase quadrature.
  • the outputs 52 and 62 of the circuits 50 and 60 are respectively connected to the inputs 65 and 66 of a comparator 68, the output 70 of which supplies the coil of a relay L1, the other end of which is connected at point 72 to the line of reference 40.
  • This relay controls the closing of a normally open contact L11 when the relay Ll is not energized.
  • the contact relay L11 itself supplies the coil of a relay L3 which, when excited, opens the contact L32 controlling the input of the amplifier A2 as we have seen previously.
  • the coil of relay L3 is supplied by a power source - V, + V to which it can be connected, either by closing the contact Lll when the relay Ll is supplied, or by closing two contacts L21 and L31 in series on a line parallel to contact Lll.
  • the contacts L31 and L21 are controlled by relays and are normally in the open position when these relays are not energized.
  • the contact L31 is controlled by the relay L3, thus playing a self-supply function of the latter when L3 has been previously excited, for example during the appearance of a voltage in the relay Ll with concomitant closure of the contact Lll .
  • the output 52 of the rectification and filtering circuit 50 is also connected to an input 75 of a comparator 78, the other input 76 of which is supplied by a potentiometer 80 which supplies it with a reference voltage v 20 .
  • the output 82 of this comparator supplies the coil of a relay L2, the other end of which is connected to terminal 72 of the reference line 40. This relay controls, when energized, the closing of the contact L21 in series with the self-supply contact L31 already mentioned.
  • the operating principle of the circuit is as follows.
  • steady state that is to say when a high alternating voltage is established between the line Lo and the earth
  • the alternating voltage v e taken from the terminals of the capacitor C2 of the divider is applied to the inputs El and E2 of the high impedance amplifier Al, due to the closing of contact L32 establishing the connection between terminal M and input El through amplifier A2.
  • the parameters of the amplifiers A2 and A3 are determined for this purpose, as a function of the nominal amplitudes of the voltages v and v i ., So that the signal on the input 65 of the comparator 68 is always greater than the signal appearing on its input 66 (v 2 > v l ), so that the output level of comparator 68 is insufficient to energize relay Ll. As a result, the contact L11 is open and the relay L3 is not supplied. Contact L21 remains in the open position, relay L2 not being energized by comparator 78 as long as v 2 remains above threshold v 20 set by potentiometer 80.
  • This situation in steady state is represented for example by the wave diagram of fig. 3 until the instant Tl, period during which the quantities v, v el (the voltage at the output of the switch L32), v 1 and v 2 are periodic.
  • this fig. 3 are also represented the positions of the contacts Lll, L32, L31, and L21, the open position of a contact being represented by a logic zero level while the closed position (case of L32 in steady state) is represented by level 1 .
  • the product of this comparison is used to disconnect the link between the capacitor C2 and the inductive load constituted by the transformer T at the output of the electronic amplifier and thus avoid saturating it. As we have seen, it is moreover better to interrupt this connection before the electronic amplifier rather than after since this thus practically avoids any discharge of the capacitor C2 and thus the modification of the charge levels Cl and C2 until resetting.
  • the choice of the value of the reference voltage v 20 is dictated by the following considerations: for a capacitive voltage transformer as described by way of example in FIG. 2 in a very high voltage network, of the type whose nominal voltage Un is 220 kvolts or 400 kV, the actual voltage present on the network can vary for example between 0.8 and 1.2 times the nominal value. Consequently, the resulting current undergoes amplitude variations comparable with respect to its nominal value In. In addition, the frequency of the networks considered is 50 Hz but it is likely to slip depending on the operating conditions between 45 and 55 Hz.
  • the minimum observable current when re-energizing a previously triggered line will be encountered in the case where the actual network voltage is equal to 80% of the nominal voltage and when the frequency is 45 Hz only.
  • the minimum value of the current likely to cross impedance Z during a reclosing is approximately 70% of its nominal value, which provides a maximum value for the choice of v 20 .
  • a high voltage line can be assimilated to a capacity and, when it is isolated by opening at its two ends and charged for example with the peak value of the network voltage, it can receive in superposition on this DC voltage a periodic voltage induced by the other phases which remain under alternating voltage.
  • the maximum amplitude of the induced voltage can reach 40% of the nominal amplitude Un and, under these conditions, the current through Z does not fall to zero but to an amplitude of 40% of In (fig 4).
  • the threshold v 20 must therefore be greater than the corresponding amplitude of v 2 '. We can therefore choose v 20 between 0.4 and 0.7 times the value of v 2 corresponding to In.
  • relays L1, L2 and their associated contacts can be produced in the form of flip-flops with semiconductors.
  • a mechanical contact actuated by relay could however be preferred for the realization of the contact L32 and of its command L3 because of its good dielectric behavior with the overvoltages at high frequencies likely to appear at the terminals of C2 during the operations of release and reclosing of the Lo line.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Current Or Voltage (AREA)
EP80400554A 1979-05-09 1980-04-23 Verbesserung kapazitiver Spannungstransformatoren mit elektronischem Ausgang Expired EP0019507B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7911690A FR2456327A1 (fr) 1979-05-09 1979-05-09 Perfectionnement aux transformateurs capacitifs de tension a sortie electronique
FR7911690 1979-05-09

Publications (2)

Publication Number Publication Date
EP0019507A1 true EP0019507A1 (de) 1980-11-26
EP0019507B1 EP0019507B1 (de) 1983-05-18

Family

ID=9225226

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80400554A Expired EP0019507B1 (de) 1979-05-09 1980-04-23 Verbesserung kapazitiver Spannungstransformatoren mit elektronischem Ausgang

Country Status (5)

Country Link
US (1) US4327390A (de)
EP (1) EP0019507B1 (de)
CA (1) CA1137556A (de)
DE (1) DE3063267D1 (de)
FR (1) FR2456327A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112285411A (zh) * 2020-10-22 2021-01-29 国网四川省电力公司电力科学研究院 Cvt非线性模型、基于模型的系统与测量电压的方法

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4577148A (en) * 1982-12-17 1986-03-18 Westinghouse Electric Corp. Surge arrester equipped for monitoring functions and method of use
JPS61116922A (ja) * 1984-11-07 1986-06-04 三菱電機株式会社 高速限流遮断器
DE3502638A1 (de) * 1985-01-26 1986-07-31 MWB Messwandler-Bau AG, 8600 Bamberg Verfahren, schaltung und einrichtung zur beseitigung der gleichspannungskomponente eines kapazitiven wechselspannungsteilers
US4731585A (en) * 1987-02-24 1988-03-15 Kabushiki Kaisha Toshiba Antenna coupling circuit for magnetic resonance imaging
FR2636434B1 (fr) * 1988-09-09 1991-01-04 Alsthom Gec Dispositif de mesure des tensions d'une installation triphasee, notamment de type blinde
FR2655736B1 (fr) * 1989-12-07 1992-01-24 Alsthom Gec Dispositif de mesure de tension.
FR2720511B1 (fr) * 1994-05-25 1996-07-05 Gec Alsthom T & D Sa Procédé et dispositif pour la suppression d'une composante perturbatrice d'un signal périodique et application à un transformateur capacitif électronique de tension.
DE10012068A1 (de) * 2000-03-14 2001-10-04 Hsp Hochspannungsgeraete Porz Vorrichtung und Verfahren zur Überwachung einer Kondensatordurchführung
US6420875B1 (en) * 2000-03-22 2002-07-16 General Electric Company CVT transient filter
GB0010720D0 (en) * 2000-05-03 2000-06-28 Ghassemi Foroozan Power quality sensors for conventional capacitor coupled voltage transformers
KR100873731B1 (ko) * 2007-03-15 2008-12-12 한국생산기술연구원 전기장을 이용한 전력변환장치
US9008982B2 (en) * 2012-03-09 2015-04-14 Schweitzer Engineering Laboratories, Inc. Systems and methods for determining residual flux in a power transformer
US20140009176A1 (en) * 2012-07-06 2014-01-09 Apple Inc. Capacitance measurement circuit
DE102014207478A1 (de) * 2014-04-17 2015-10-22 Robert Bosch Gmbh Verfahren und Vorrichtung zur Ermittlung eines Isolationswiderstandes sowie Hochvoltbatteriesystem mit einer solchen Vorrichtung
US10802054B2 (en) 2017-09-22 2020-10-13 Schweitzer Engineering Laboratories, Inc. High-fidelity voltage measurement using a capacitance-coupled voltage transformer
CN111108399A (zh) 2017-09-22 2020-05-05 施瓦哲工程实验有限公司 使用电容耦合电压互感器中的电阻分压器的高保真度电压测量
US11038342B2 (en) 2017-09-22 2021-06-15 Schweitzer Engineering Laboratories, Inc. Traveling wave identification using distortions for electric power system protection
US11187727B2 (en) 2019-04-29 2021-11-30 Schweitzer Engineering Laboratories, Inc. Capacitance-coupled voltage transformer monitoring

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2118182A1 (de) * 1970-12-18 1972-07-28 English Electric Co Ltd
DE2634595A1 (de) * 1975-08-05 1977-03-03 Gen Electric Geraet zur ueberwachung hoher wechselspannungen

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3870926A (en) * 1970-12-18 1975-03-11 English Electric Co Ltd Capacitor voltage transformer system
GB1585488A (en) * 1977-05-11 1981-03-04 Gen Electric Apparatus for monitoring high alternating voltages

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2118182A1 (de) * 1970-12-18 1972-07-28 English Electric Co Ltd
DE2634595A1 (de) * 1975-08-05 1977-03-03 Gen Electric Geraet zur ueberwachung hoher wechselspannungen

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112285411A (zh) * 2020-10-22 2021-01-29 国网四川省电力公司电力科学研究院 Cvt非线性模型、基于模型的系统与测量电压的方法
CN112285411B (zh) * 2020-10-22 2023-05-02 国网四川省电力公司电力科学研究院 Cvt非线性模型、基于模型的系统与测量电压的方法

Also Published As

Publication number Publication date
CA1137556A (en) 1982-12-14
DE3063267D1 (en) 1983-07-07
US4327390A (en) 1982-04-27
FR2456327A1 (fr) 1980-12-05
FR2456327B1 (de) 1982-09-24
EP0019507B1 (de) 1983-05-18

Similar Documents

Publication Publication Date Title
EP0019507B1 (de) Verbesserung kapazitiver Spannungstransformatoren mit elektronischem Ausgang
EP0133128B1 (de) Überstromschutzeinrichtung
EP0407310B1 (de) Festkörperauslöser mit einer Desensibilisierungsvorrichtung für den Erdschutz
EP3232526A1 (de) Vorrichtung zur detektion eines fehlerstroms
FR2942352B1 (fr) Identification et protection d'un systeme de courant c.a-c.c aerospatial en presence de contenu de courant c.c en raison des charges defectueuses
EP0051820B1 (de) Schaltung zur schnellen Ableitung einer Restladung auf einem zur Überwachung hoher Wechselspannungen verwendeten kapazitiven Spannungsteiler
FR3044836B1 (fr) Dispositif de protection differentielle du type b ou b+ comportant deux modules en parallele et en concurrence
EP1845383B1 (de) Verfahren zur Erkennung der Sättigung eines Stromtransformators
FR2954613A1 (fr) Dispositif et procede de protection differentielle et appareil electrique comportant un tel dispositif
CH621895A5 (de)
FR2862423A1 (fr) Dispositif et procede de protection differentielle et appareil electrique comportant un tel dispositif
FR2520165A1 (fr) Interrupteur differentiel a usage domestique
EP3471228A1 (de) Vorrichtung und verfahren zum differentialschutz, und eine solche vorrichtung enthaltendes elektrisches gerät
CA2042485A1 (fr) Procede de limitation d'une surcharge base sur la technique de controle pwm (ou lc3) et dispositif electronique de mise en oeuvre de ce procede
EP3707796B1 (de) Differenzialschutzvorrichtung mit filterung des trägers des erregungssignals
EP1003263B1 (de) Differentialschutz
EP0814555B1 (de) Differentialschutz
CA3004694A1 (fr) Procede et dispositif de mise sous tension d'un transformateur de puissance
EP4216386A1 (de) Schutzvorrichtung für eine elektrische anlage in wechselstrom und/oder gleichstrom
EP1083644B1 (de) Lichtbogenstromsensitiver Erdfehlerschutz, Auslöser und Schutzschalter mit einer solchen Vorrichtung
EP1629598B1 (de) Statische sichere ausgabestufe
FR2601524A1 (fr) Procede de surveillance des defauts internes d'un equipement electrique et dispositif pour la mise en oeuvre de ce procede
FR2775847A1 (fr) Dispositifs de protection differentielle, appareil electrique et installation electrique comportant un tel dispositif
EP0914700B1 (de) Verfahren und vorrichtung zur aufrechterhaltung der elektrischen stromversorgung in einem elektrischen mehrphasigen energieverteilungsnetz
CH648158A5 (fr) Circuit et installation de protection d'une ligne d'alimentation d'electricite.

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): BE CH DE GB IT NL SE

17P Request for examination filed

Effective date: 19810428

ITF It: translation for a ep patent filed

Owner name: BARZANO' E ZANARDO MILANO S.P.A.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): BE CH DE GB IT LI NL SE

REF Corresponds to:

Ref document number: 3063267

Country of ref document: DE

Date of ref document: 19830707

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 19890124

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19890126

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19890131

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19890313

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19890330

Year of fee payment: 10

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19890430

Year of fee payment: 10

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19900423

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19900424

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Effective date: 19900430

Ref country code: CH

Effective date: 19900430

Ref country code: BE

Effective date: 19900430

BERE Be: lapsed

Owner name: ENERTEC S.A.

Effective date: 19900430

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Effective date: 19901101

NLV4 Nl: lapsed or anulled due to non-payment of the annual fee
GBPC Gb: european patent ceased through non-payment of renewal fee
REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19910101

ITTA It: last paid annual fee
EUG Se: european patent has lapsed

Ref document number: 80400554.4

Effective date: 19910115